The present invention relates to reel-to-reel tape transports, and more particularly to the storage and handling of magnetic tape.
One of the predominant formats for magnetic tape recording and playback devices is the reel-to-reel system. In such devices, tape is stored on a reel including a circular cylindrical core structure onto which the tape is wrapped. The tape includes a base material, which takes the form of a thin web of polyester or like composition, combining the characteristics of limpness and high tensile strength. This base is coated with a layer of magnetic particles dispersed in a suitable binder.
Magnetic recording has been applied to a wide array of applications, many of which impose demanding requirements as to the quality of manufactured tape, and in regard to maintaining tape integrity during use and storage. For example, computer tapes are subject to rigorous specifications as to avoidance of "dropouts", or errors in the recording medium. These tapes, and the transport apparatus, must be designed to permit rapid shuttling of the tape without significant mechanical defect. Instrumentation tapes and their transport systems also undergo rigorous testing for mechanical and electromagnetic defects, as do video tapes.
Magnetic tape base materials are vulnerable to various types of mechanical defect. Common shortcomings are "cupping", which imparts an undesirable stiffness to the tape due to nonuniformities in the base film; "curling", which is manifested in a tendency of free hanging tape to twist; and layer-to-layer adhesion. These defects may result from improper manufacture, or from problems in storing or handling the tape. The user may also encounter an uneven "pack" or winding of the tape, such as a local protrusion of certain layers of the tape, which may lead to nicked or torn edges. "Cinching" is likely to occur in a loosely-packed tape, and refers to a tangential slippage between layers which in extreme cases can cause folding or creasing of the tape.
It is often necessary or desirable for the user to discard a portion of the magnetic tape wound upon a reel, because of mechanical defects such as those discussed above, defects in the magnetic coating, or for other reasons. In some cases it is even desirable to discard an entire roll of tape wound upon an expensive reel, while saving the reel for later use. In such instances, it is desirable to employ some device for efficiently stripping the tape section from the reel, and discarding the tape. Prior art devices for this purpose have featured elaborate and cumbersome techniques.
Accordingly, it is a principal object of the invention to provide apparatus for stripping magnetic tape from reels efficiently and reliably. Desirably such apparatus should be simple in construction and use.
Another object is to achieve a device for this purpose which is compatible with a variety of types of recording tape and reel dimensions. As a related object, such a device should be adaptable to a variety of reel-to-reel magnetic tape applications.
Still another object is to provide inexpensive, easily manufactured apparatus of this nature. Desirably, such apparatus should be routinely adaptable to the specifications of given reel-to-reel tape transport systems.
A further object in the invention is that such a device be reusable.